In a toilet installed in a house, family office or the like, a flush toilet which is connected to a water supply pipe and a sewage pipe is the mainstream for environmental utility and improvement of hygiene. The flush toilet has a reservoir tank which temporarily stores water and a stool which is connected to the reservoir tank. When a user discharges raw sewage into the stool, the raw sewage can be forced to flow into the sewage pipe by discharging water from the reservoir tank. When the water supply pipe is connected to the reservoir tank, the raw sewage can be forcibly discharged to the sewage pipe, thereby facilitating the disposal of the raw sewage.
In the disposal of raw sewage in the flush toilet, it is possible to discharge a large amount of water from the reservoir tank, thereby discharging a raw sewage and at the same time cleaning the inner wall of the stool. As mentioned above, in the flush toilet, the discharge of the raw sewage and the cleaning of the stool can be performed at the same time so that the flush toilet can be easily controlled. Even if the inner wall of the flush toilet is dirty, dirt can be cleaned by a brush, etc. by flushing water from the reservoir tank since the water is always supplied from the water supply pipe to the reservoir tank. As a result, the cleaning of the stool can be easily accomplished if there is a supply of water from the water supply pipe even if the cleaning is manually performed.
However, there are many houses having no flush toilet, and such toilet connects to a purifying tank or a night soil tank since water supply and sewage pipes are not installed. In such a toilet, self-cleaning cannot be performed since tap water is not supplied to the toilet. Furthermore, since the purifying or night soil tank is connected to the stool, even if the large amount of tap water is flushed into the stool, the tap water is forced to flow into the purifying tank or night soil tank, and hence the dirt on the stool cannot be flushed by the tap water.
In the toilet which is installed in a transportation facility such as vessels, airplanes or trains, a reservoir tank fixed to the transportation facility and a stool are connected to each other and raw sewage discharged to the stool is accommodated in the reservoir tank until the transportation facility reaches its destination. The reservoir tank is limited in its size because the capacity thereof is designed to merely accommodate the raw sewage in view of the structural demand of the transportation facility. Under the circumstances, a large amount of cleaning water cannot be flushed into the stool. In such a stool, the dirt stuck to the stool cannot be satisfactorily flushed using the cleaning water.
In a temporary toilet which has been temporarily installed in a disaster area or a construction site, the reservoir tank is also limited in its capacity. It has been difficult to employ the structure for flushing the raw sewage and dirt using the cleaning water such as in a flush toilet. Accordingly, it has been difficult to discharge a large amount of water into the stool so as to clean the stool even if the stool is dirty.
Accordingly, in the cleaning of toilet stools of the aforementioned types, the stool is normally cleaned manually, the cleaning operation is unhygienic, and hence modernization thereof has been required.
Under the circumstances, there has been proposed a stool wherein the inner wall of the stool is covered with bubbles which are stuck thereto and the raw sewage is dropped on the bubbles. In such a stool, the raw sewage does not contact directly the stool and dirt is not generated on the inner wall of the stool since the raw sewage is discharged together with the bubbles so that the stool is always kept clean. There have also been proposed cleaning mechanisms for generating bubbles to prevent the stool from becoming dirty.
However, in the stool having a cleaning mechanism for generating bubbles, the generated bubbles are jetted from a discharge port formed in part of the stool so that the bubbles are stuck merely to a central portion or near a central portion of the stool so that the bubbles cannot be stuck to the periphery of the inner wall. Accordingly, raw sewage is not prevented from being stuck to the peripheral surface of the inner wall of the stool. Further, in the stool having such cleaning mechanism using bubbles, the raw sewage can be dropped into a drain or sewage pipe by the bubbles, but toilet paper or other foreign matter which has been used cannot be flushed. Accordingly, if toilet paper or foreign matter is stuck to the stool, it must first be moved manually using a brush, etc. and then removed from the stool.
The present invention, which has been made so as to overcome the aforementioned problems, injects air bubbles into the cleaning water so as to generate bubbles and then flows the thus generated bubbles inside the entire inner wall of the bowl of a stool, thereby covering the inner bowl by the bubbles. When the bubbles are stuck to the entire inner wall of the stool, the raw sewage discharged into the stool is always covered with the bubbles, thereby preventing the raw sewage from being stuck to the stool. Furthermore, even if toilet paper or foreign matter is dropped onto the inner bowl, cleaning water is forcibly flushed after the discharge of the raw sewage so as to discharge the toilet paper or foreign matter into the drain or sewage pipe, thereby dispensing with a further cleaning operation after the discharge of the raw sewage.
The present invention is to provide a cleaning mechanism for a stool which comprises an outer cover having a bottom part and an upper opening, an inner bowl which is accommodated inside the outer cover for receiving raw sewage and spaced from the outer cover so as not to contact the outer cover, a substantially frame-shaped upper cover having a periphery which is brought into contact with an upper end of the outer cover, a lower surface which is spaced from an upper end peripheral edge of the inner bowl and a central introduction hole through which raw sewage is introduced into the inner bowl, wherein cleaning water is interposed in a space between the outer cover and the inner bowl, the cleaning water being mixed with a foaming material, and air discharge bodies provided inside the bottom part of the outer cover for receiving air supplied from outside and spouting the air.
According to the present invention, the stool has an outer casing comprising the outer cover and upper cover the inner bowl is accommodated between the outer and upper covers for receiving the raw sewage. A large evacuation opening is defined on the central portion of the upper cover for exposing the inner wall of the inner bowl and the inner side of the ring-shaped periphery of the upper cover is spaced from an upper end peripheral edge of the inner bowl. Cleaning water containing a foaming material such as a surface active agent is reserved between the outer cover and inner bowl. If air is introduced under the cleaning water, bubbles are generated in the cleaning water so that the bubbles filled the region between the outer cover and inner bowl. When the bubbles rise, they flow from the upper end peripheral edge of the inner bowl toward the inner wall of the inner bowl so that the entire inner wall of the inner bowl is covered with the bubbles.
In the state where the bubbles are stuck to the entire inner wall of the inner bowl, when the raw sewage is dropped from the large evacuation opening into the inner bowl, the raw sewage is covered with the bubbles so that it does not contact the inner wall of the inner bowl. When the raw sewage has been discharged, the cleaning water is jetted from an ejector along the inner peripheral surface of the inner bowl, and the raw sewage can be dropped together with the bubbles. At this time, the raw sewage, toilet paper and foreign matter are floated by the bubbles and can be slid along the inner bowl and dropped into the drain or sewage pipe because of the high fluidity. In such manner, the raw sewage does not contact the inner wall of the inner bowl and dirt does not stick thereto. Accordingly, the stool is always kept clean, which dispenses with the manual cleaning operation.